In the drive train system disclosed in the present application, it was important to develop a crank arm which would operate within a confined space. This was necessitated by a confined space available to position the present system in some applications. Because of this and because of related space needs within the housing for the system, the present system would not permit a crank arm which would protrude substantially beyond a drive screw in the system or which would project beyond a predetermined position of an axle being rotated by the system. Accordingly, the sliding crank arm of the present invention was developed.
The present invention is a sliding crank actuator for rotating an axle connectable to the actuator, the axle being provided as part of a system external to the actuator. The axle is rotatable in the external system about an axis which is located at a fixed distance from and which is perpendicular to a drive screw in the actuator.
The actuator comprises a drive screw rotatable about a fixed axis and a drive nut on the drive screw. The drive nut moves along the length of the drive screw as the drive screw is rotated.
The actuator further comprises a crank arm having a first member and a second member slideably innerconnected so that the first and second members slide longitudinally with respect to each other. The first member is connected to the drive nut so that the crank arm can pivot about the drive nut. The second member comprises apparatus for connecting the second member to the axle so that, as the drive nut moves along the drive screw, the axle connected to the second member is rotated. The first member of the crank arm slides along the second member of the crank arm as the drive nut moves and the axle turns.